That's fine. A lot of people don't pursue relationships with cis women or cis men who are unable to reproduce. But it's not exactly an argument you can make for one night stands or relationships in which it isn't the goal to reproduce. Unless you somehow can only find women who are capable of reproducing physically attractive.
You are correct if we were to go on the premise that the goal isn't to reproduce. Personally though I am at a point in life where reproducing is my goal. I'm 32 and have no kids, and I want to change that. To me, that means that every date I go on has to have the potential for long term relationship, marriage, and eventually, children. This is just a preference for dating though, and if I were to go with someone who is trans, I'd like to know from the get go for that very reason.
That is a bit separate to the topic at hand though, even if it is fair to connect it (because I think that is the eventual goal of the OPs question). Other than my preference for dating, a trans woman is a woman, and I can't quantify how 'womanly' they are. Sex doesn't matter - a friend is gender neutral.